Functional nonwoven fabric and manufacturing method therefor

Abstract

The problem addressed by the present invention is to suppress a decrease in air permeability of a nonwoven fabric while suppressing falling off of functional particles. The means for solving the problem of the present invention is that a functional nonwoven fabric 1 is formed to contain long fibers made of synthetic resin and integrated with functional particles 4, 4 having a predetermined function. A diameter of the long fiber changes in a longitudinal direction of the fibers so that a plurality of large diameter portions 2, 2 and a plurality of small diameter portions 3, 3 are alternately arranged. The small diameter portions 3, 3 are monofilaments formed of the synthetic resin. At least a part of the large diameter portions 2, 2 contain the functional particle 4. A fiber diameter of the small diameter portions 3, 3 is equal to or smaller than a diameter of the functional particles 4, 4 contained in the large diameter portions 2, 2.

1 . A functional nonwoven fabric comprising long fibers made of synthetic resin and integrated with a functional particle having a predetermined function, wherein
 the functional particle is a particle having thermal expansion properties,   a diameter of the long fiber changes in a longitudinal direction of the long fiber so that a plurality of large diameter portions and a plurality of small diameter portions are alternately arranged,   the small diameter portion is a monofilament formed of the synthetic resin,   at least a part of the large diameter portion contains the functional particle, and   a fiber diameter of the small diameter portion is equal to or smaller than a diameter of the functional particle contained in the large diameter portion.   
     
     
         2 . The functional nonwoven fabric according to  claim 1 , wherein at least a part of the large diameter portion is formed by solidifying a plurality of the functional particles into a string-like or dumpling-like shape with the synthetic resin. 
     
     
         3 . The functional nonwoven fabric according to  claim 2 , wherein the fiber diameter of the small diameter portion is 1/100 or more of the diameter of the functional particle. 
     
     
         4 . The functional nonwoven fabric according to  claim 3 , wherein
 the fiber diameter of the small diameter portion is 100 nanometers or more and 10 micrometers or less, and   the diameter of the functional particle is 300 nanometers or more and 200 micrometers or less.   
     
     
         5 . (canceled) 
     
     
         6 . The functional nonwoven fabric according to  claim 1 , wherein the functional particle is an aluminum phosphite particle. 
     
     
         7 . (canceled) 
     
     
         8 . The functional nonwoven fabric according to  claim 1 , wherein
 the functional nonwoven fabric is a functional nonwoven fabric having thermal expansion properties, and   the long fiber is configured so that the plurality of large diameter portions and the plurality of small diameter portions are alternately arranged in the form of a string of beads.   
     
     
         9 . The functional nonwoven fabric according to  claim 8 , wherein the functional particle is an aluminum hydrogen phosphite particle. 
     
     
         10 . The functional nonwoven fabric according to  claim 8 , wherein
 the large diameter portion is string-like or dumpling-like, and   the functional particle is integrated with the large diameter portion by being wrapped in the synthetic resin in a film, net, or fiber bundle form, or by being bonded with the synthetic resin.   
     
     
         11 . The functional nonwoven fabric according to  claim 8 , wherein the fiber diameter of the small diameter portion is 1/100 or more of the diameter of the functional particle. 
     
     
         12 . The functional nonwoven fabric according to  claim 11 , wherein
 the fiber diameter of the small diameter portion is 100 nanometers or more and 10 micrometers or less, and   the diameter of the functional particle is 300 nanometers or more and 200 micrometers or less.   
     
     
         13 . A method for manufacturing the functional nonwoven fabric according to  claim 1 , the method comprising:
 a first step of dispersing functional particles in a synthetic resin liquefied by heat melting or by dissolving in a solvent, and   a second step of, following the first step, forming the nonwoven fabric while spinning long fibers from the liquefied synthetic resin containing the dispersed functional particles by a melt-blowing method or an electrospinning method.